With crystalline silicon modules dominating the PV industry for a while, new promising technologies have been emerging now and then. A relatively new addition to the list is perovskite solar cell technology. To all those who are new to perovskite technology, they are organometal lead halide based cell technology with the ability to absorb sunlight and convert it into electricity just like silicon cells. It was first reported in the year 2009 by Kojima et al., proving to be a major breakthrough in the field of photovoltaics.
The initial efficiency of perovskite solar cells was relatively low at 4 % but with rapid progress in the research, the latest perovskite cells are now 21 % efficient, very much comparable with silicon cells which are 25 % efficient. It should be noted that perovskite solar cells took just 7 years to get past 20 % efficiency mark while it took more than 60 years of rigorous research for silicon scientists to make Si cell technology 25 % efficient.
According to National Renewable Energy Laboratory (NREL), “A new solar material that has the same crystal structure as a mineral first found in the Ural Mountains in 1839 is shooting up the efficiency charts faster than almost anything researchers have seen before and it is generating optimism that a less expensive way of using sunlight to generate electricity may be in our planet’s future.” Well, that’s quite a word.
Another big advantage of perovskite solar cell is that it can convert sunlight into electric current even with a lot of material defects while in the case of a silicon cell, nanoscale defects at ionic level are sufficient enough to dissipate sunlight even before producing electrons. With this advantage in hand, perovskite cells could be manufactured at a much cheaper cost than a silicon cell.
Given its impressive track record at the laboratory level research, what’s stopping it from hitting the mass markets? The instability of crystal structure at room temperature and degradation over prolonged period of light exposure still remains a concern.
The latest in the series of breakthroughs which might help its commercialization, comes from a research group in Ulsan National Institute of Science and Technology, Korea. The team led by Prof. Sang-II Seok developed perovskite cells using a new manufacturing technique named ‘Hot Pressing Method’. The cells produced by this method exhibited photo-stability and retained 93 % of its initial performance after 1000 hours of sunlight exposure.
According to Lux Research report in 2016, “perovskite cell technology is likely to be commercialized somewhere between 2019 and 2021 owing to improving technology and emerging university + commercial partnerships”.
About the question of perovskite solar cell commercialization, we have to totally agree with Tyler Ogden, a Lux Research associate who states, “While the efficiency question has been answered, there remain issues in stability, cost, and the feasibility of real-world efficiencies that must be addressed before commercialization can occur”.